Method and apparatus for producing sheet glass



July 21, 1931.

Filed Nov. 15

9 it :L mntot Joseph CI. !Peace 'Patented July 21, 1931 UNITED STATES PATENT OFFE I 4 i i JOSEPH A. REECE, OF TOLEDO, OHIO, ASSIGNOR TO LIBBEY-OWENS-FO RD GLASS COM:-

' PANY, OF TOLEDO, OHIO, A CORPORATIQN OF OHIO METEO!) AND PPAR-ATUS FOR PRODUCING SHEET GLASS Application filed November l, 1926; Serial No. 148,&48.

This invention is an improvement in the art of producing sheet glass, and has more particular reference to' a method and apparatus for forming a continuous sheet.

An important object of the invention is` to provide, inthe art of producing sheet glass, means for conditioning the temperature of a continuously moving stream of molten glass before reducing it to sheet form.

Another object of the invention is to provide, in the art of producing sheet glass,

' means for uniformly controlling the temperature of a stream of molten glass formed underpressure, and means for reducing said stream to sheet form.

A further object of the invention is to pro- -vide, in the art of producing sheet glass,

means for causing a continuously moving sheet of molten glass to be of a substantially uniform temperature throughout its entire area at the beginning of thei annealing operation.

provide, in the art .of producing sheet glass, means for reducng a continuously moving stream of molten glass to sheet form, 'means -for annealing said sheet, and means for conditioning the temperature of the stream of molten glass before it is reduce'd to sheet form in order that the resultant sheet will be of a substantially uniform temperature throughout its entire area atthe beginning of the annealing operation.

Stil-l another and important object of the invention to provide; in the art of producing sheet glass, the method of forming a sheet which consists in conditioning the temperature of a continuouslv moving stream of molten glass formed un er pressure, reducing said stream to sheet form, and subsequently annealing said sheet.

Other objects and advantages of the invention will become more apparent during the course of the following description when taken in connection with the accompanying drawings.

In the drawings forming a part of this application and wherein like numerals are employed to designate like parts throughout the same, e

4 Fig. 1 is a vertical longitudinal section through improvedmheet glass apparatus constructed in accordance with the present invention, and

F igs. 2 and 3 illustrate slightly modified forms of the present invention.

' Referring now more in detail to the acconpanying drawings, andmore especially to' Fig. 1, the nuneral 5 designates the exit end of a glass' melting furnace of any desired Construction, and within which the glass batch containing the ingre-dients from which the nol'ten glass iscproduced is nelted to form the mass of molten glass 6.' The end Wall 7 of the tani( is provided with a relatively large outlet opening 8, and positioned in advance of the said opening is a housing '9. Arranged within the housing 9 is a horizontal annular or rectangular partit-ion wall 10 which divides the interior thereof into a heating chamber 11 and a somewhat larger condtioning chamber 12. A further object of the invention s to Posi-tioned between the housing 9 and the tank 5, and closing a greater portion of the opening 8, is a refractory member 13 'provided with' a horizontal slot 14 defined by a pair ofspaced lips 15. These lips are (lis rected outwardly as shown, and are provided with mctallic Caps 16 formed of a suitable 'ditioning chamber 12. This stream is suported within the said chamber upon the iorizontally aligned rollers 17, and as it issues from the said chamber through a slot 20 in the outer end wall thereof, itis passed j between the rolls 18 which serve to' reduce the said stream to sheet form as indicated at 21. This sheet 21 is then carried along upon a plurality of rollers 22 into an annealing leer 23 where the said sheet is gradually reduced to room temperature as is well known Arranged within the heating chamber 11- are any preferred number of suitable gas burners or the like 24, and the gas issuing froni these burners serves to heat the partition wall 10. This heat radiated through the wall' 10 into the conditioning chamber 12 is distributed evenly onto the stream of molten glass 19. With such an arrangement, the stream of molten. glass 19 will be so conditioned that it will be of a substantially uniform 'temperature throughout its entire area as it passes to the sheet forming rolls 18, and consequently the "sheet 21 will also be of substantially auniform temperature throughout its entire area as it enters the annealing leer. Thus, undesirable strains in the glass as it passes through the said leer will be reduced to a ninimum and obviously, better annealing of the sheet can be obtained when the temperature thereof is substantially' uniform than When the area of said sheet is at differe'nt temperatures. The present invention therefore embodies means for forming a `"stream of molten glass under head pressure,

means for uniformly controlling the temperature thereof and means for reducng sad stream to sheet form.

In Fig; 2, wherein hasbeen shown a slightly modified form of the present invention, the lips 15, instead of being directed outwardly are directed i-nwardly into the `molten glass 6 so that the sub-surface glass is received somewhatback into the tank instead of atthe 'end-thereof. As shown, the refractory meinber 13 is arranged within the openings`8 instead of in advance thereof as illustrated in.

Fig. 1. Again, in this form .of the invention,

there is arranged within the heating 'chamber 11 a inember 25 provided with a pl'urality of outlet openings 26 and with a stack 27 for drawing the waste products of c'ombistion' exteriorly of the said heating chamber.

In the form of the invention shown in Fig.

3, the stream of molten glass, instead of being supported upon a plurality of'horizontally aligned rollers, is supported upon and. carried along by means of an endless conveyor 28 trained about rolls 29carried by shafts 30.

It is 'to be understood that the form of the invention herewith shown and described is to v be taken as the 'preferred embodiment of the same, and that various changes in the sh ape,

of substanti'ally and projecting rearwardly within the tank and having a slot therein beneath the level of said molten'glass, a housing mounted in opp'osition to said member, a 'partition wall within the housing' dividing the interior thereof into a heating chamber and a some what larger conditioning chamber, rotatable -taining a mass of molten glass and having an end wall, a member arranged within said wall and projecting rearwardly within the tank andhaV ing a slot therein beneath the level of said molten glass, a housing mounted in op- 'position to said member and divided interiorly into a conditioning chamber and a sur-- rounding heating chamber, movable means within the conditioning chamber for receiving a stream of molten lass issuing .from said slot and carrying it through said chamber in a generally horizontaldirection, means for'heating the heating chamber, and means for receiving the stream of molten glass and reducing it to a sheet of substantially termined and uniform thickness.

3. -Insheet glass apparatus, a tank containing a mass of molten glass and provided with an end wall having a slot therein,- saidslot being positioned inwardly of the end of the i tank, and beneath the level of the molten glass, a housing mounted in opposition to said slot and divided interiorly into a condition-- ing chamber and a surrounding' heating chamber, movable 'means within the condi- 'tioning chamber for receiving the stream of molten-glass issuing from said slot and carry-` ing it through' 'said chamber in a generally means for heating the horizontal direction d means for receiving the heating chamber, an

stream of molten glass as it leaves the conditioning chamber and reducing it to a sheet predetermned and uniforn thickness.

Signed at Toledo, in thecounty of Lucas and 'State of Ohio, this 12th day of November, 1926. a

. JOSEPH A.-

size and arrangement of parts may be re-- claims.

Claims 1) Insheetglass appar'atus, a tank con'- taining a mass of molten glass and having an end wall, a member arranged within said wall 

